The present invention relates to devices for injecting, dispensing, administering, delivering or infusing substances, and to methods of making and using such devices. More particularly, the present invention relates to such devices comprising one or more of the following components or features: a rod or rod-like member which may be threaded and thought of or referred to as a plunger rod; a real-time display for displaying various quantities of a substance, e.g., the quantity to be injected or dispensed, the quantity available for dispensing, the quantity dispensed, etc.; a mechanical lock for use prior to mixing an ampoule, possibly a 2-chamber ampoule; a guide for the rod or rod-like member; and a claw lock.
In some embodiments of injection devices, to set or select the quantity of a substance to dispensed, a setting movement is performed on a setting element. The setting element may be a dose setting knob or a dose setting ring and the setting movement may be a rotating or turning movement of the knob or ring wherein the extent of the rotation, in other words, a rotation or rotational angle, defines what quantity of substance will be dispensed from the injection device in an injection operation. In the case of injection devices designed to dispense a fixed and possibly pre-set quantity of a substance, for example, fixed-dose injection pens, the setting movement may be effected to prime the device for dispensing a pre-defined dose.